ObjectiveTo observe the application of ultra wide angle FFA (UWFA) in the study of the correlation between diabetic macular edema (DME) and retinal ischemia.MethodsOne hundred and forty-five patients (220 eyes) with diabetic retinopathy (DR) diagnosed by fundus and FFA in Shaanxi Eye Hospital from January to August in 2018 were enrolled in the study. There were 132 eyes from 85 males and 88 eyes from 60 females. The average age was 54.87±10.89 years old, 171 eyes were non proliferative DR (mild 27 eyes, moderate 32 eyes, severe 112 eyes), 49 eyes were proliferative DR. There were 141 eyes with retinal ischemia. None of them received retinal laser photocoagulation, intravitreal injection of drugs and other eye surgery. UK Optomap200Tx imaging system was used for UWFA examination. According to whether the central macular retina of 2 disc diameter area was involved, the eyes were divided into DME group (183 eyes) and non DME group (37 eyes). According to different appearance of fluorescein leakage in macular zone, DME group was further divided into focal leakage (FL) group, diffuse leakage (DL) group and diffuse cystic leakage (DCL) group, with 94, 73 and 16 eyes, respectively. The incidence of retinal ischemia, retinal neovascularization (RNV) and/or NVD were compared between DME group and non DME group, and the difference of retinal ischemia index (IIS) of three macular edema subgroups was further compared. The differences of retinal ischemia, RNV and/or NVD between DME group and non DME group were compared by chi square test or Fisher exact probability method. The different retinal IIS of three macular edema subgroups was compared by one-way ANOVA.ResultsAmong 183 eyes in DME group, 132 eyes (72.13%, 132/183) were accompanied with retinal ischemia, and 9 eyes (24.32%, 9/37) were accompanied with retinal ischemia in non DME group. There was significant difference in the incidence of retinal ischemia between the two groups (χ2= 30.56, P＜0.05). In FL group, DL group and DCL group, there were 51 (54.26%, 51/94), 70 (95.89%, 70/73) and 11 (68.75%, 11/16) eyes with retinal ischemia, and 11 (11.70%, 11/94), 30 (41.10%, 30/73) and 4 (25.00%, 4/16) eyes with NVD and/or RNV, respectively, The retinal ischemia indexes of these three groups were 0.0516±0.0961, 0.2192±0.2166, 0.1244±0.1460. There were statistically significant differences in the incidences of retinal ischemia (χ2=35.53), NVD and/or RNV (χ2=18.50) and retinal ischemia indexes (F=22.80) among the three groups (P=0.000 0, ＜0.050 0, ＜ 0.000 1).ConclusionsUWFA can dynamically evaluate the retinal ischemia in DME patients, and the enlargement of ischemic area. The formation of RNV are more likely to form DL macular edema.